Which of the following medications is used to treat irregular heart rhythms?

Anti-arrhythmia agents are specifically designed to treat irregular heart rhythms, also known as arrhythmias. These medications help to stabilize the electrical activity of the heart, which can become disrupted, leading to conditions like atrial fibrillation, tachycardia, or bradycardia. By restoring normal heart rhythm, anti-arrhythmia agents can reduce symptoms associated with these conditions, such as palpitations, dizziness, and risk of stroke.

In contrast, anti-anginal agents focus on relieving chest pain by improving blood flow to the heart muscle, primarily used in cases of angina pectoris. Congestive heart failure agents aim to manage symptoms and improve heart function in patients with heart failure but do not directly address arrhythmias. Anti-coagulation agents are used primarily to prevent blood clots, often in patients who have certain arrhythmias to mitigate the risk of stroke; however, they do not treat the underlying rhythm issue. Therefore, anti-arrhythmia agents are the clear choice when discussing treatment for irregular heart rhythms.